Machine for engraving on curved metallic surfaces

ABSTRACT

A piercing machine for marking writings, numbers and the like on metallic curved surfaces, such as the ogive-shaped portion of steel cylinders, which allows for the marking by engraving also of symbols varying from one piece to be marked to another, without hand substitution of the piercer elements. The piercers are disposed and held on a disc along a spiral arrangement. This disc may be operated and driven into rotation by two independent mechanisms, one for the engraving of the symbols which are always the same, and the other for the variable symbols. The first mechanism causes and intermittent mono-directional rotation movement, while the second mechanism causes a continuous rotation, in both the senses. The disc bearing the piercers can be brought into rotation alternatively by only one of said two mechanism, but in any case, during its rotation, it is also subjected to a rectilinear translation which, combined with the rotation, is such that the piercers disposed along a spiralshaped line, are always aligned with a hammering means the operating axis of which is stationary.

I [75] Inventor:

United States Patent [191 Groppini 1 MACHINE FOR ENGRAVING ON CURVED METALLIC SURFACES 30 Foreign Application Priority Data Dec. 29, 1971 Italy 33054/71 [52] U.S. Cl l97/6.7, 1 0l/4, 101/18,

' t 101/35 [51] Int. Cl. B4lj 1/30, B41f 1.7/18 [58] Field ofSearch 101/35, 4, 19,38, 18, 101/26, 29; l97/6.2, 6.4, 6.6, 6.7, 92, 94, 82,

[56] References Cited UNITED STATES PATENTS 1,145,832 7/1915 Donning 197/85 1,625,890 4/1927 Hokanson..." 197/94 X 2,003,211 5/1935 Michelsen 197/82 2,438,271 3/1948 Curtis l97/6.6 2,579,763 l2/1951. Schremp... 197/82 2,908,218 10/1959 Stephan 101/38 R 2,920,556 1/1960 Medertet al. 101/38 R 3,019,725 2/1962 Freeman [01/38 R 3,029,920 4/1962 Siefried 197/6.6 3,054,494 9/1962 -Rizzetti l97/6.2 X 3,160,092 12/1964 Eisen lOl/35 X 3,174,426 3/1965 Boekeloo et a1.. 101/35 X 3,249,044 .'5/l966 .Karlyn ..L 101/38 3,330,396 7/1967 James l97/6.4 3,356,199 12/1967 Robinson 197/54 1 Oct. 8, 1974 Primary Examiner-Robert E. Pulfrey Assistant Examiner-Paul .1 Hirsch Attorney, Agent, or Firml(enyon Kenyon Reilly Carr & Chapin 571 ABSTRACT A piercing machine for marking writings, numbersand the like on metallic curved surfaces, such as the ogiveshaped portion of steel cylinders, which allows for the marking by engraving also of symbols varying from one piece to be marked to another, without hand substitution of the piercer elements. The piercers are disposed and held on a disc along a spiral arrangement. This disc may be operated and driven into rotation by two independent mechanisms, one for the engraving of the symbols which are always the same, and the other for the variable symbols. The first mechanism causes and intermittent mono-directional rotation movement, while the second mechanism causes a continuous rotation, in both the senses. The disc bearing the piercers can be brought into rotation alternatively by only one of said two mechanism, but in any case,

during its rotation, it is also subjected to a rectilinear translation which, combined with the'rotation, is such that the piercers disposed along a spiral-shaped line, are always aligned with a hammering means the operating axis of which is stationary- 8 Claims, 5 Drawing Figures PATENTED BET 81974 SHEET 10F 4 PAIEmgnnm aim 3,840,104 SHEET 2 OF 4 PATENTEDUBT 819M 3.840.104

. SHEET MUF MACHINE FOR ENGRAVING ON CURVED METALLIC SURFACES BACKGROUND OF THE INVENTION Several kinds of machines are known, suitable for marking through engraving, by means of piercers, cylinders on the so-called ogive portion, the shape of which is given by the rotation of a profile with a circumferential arc configuration, around the axis of the cylinder. The radius of said arc may be slightly smaller, equal or slightly greater in size than the radius of the cylindric body of the cylinder itself. In the known machines, the piercers which are made out of steel and have at one end a given alphabetical or numerical sign or a design mark, are placed one after the other along the circumference of a disc rotating around its own axis, or are placed side by sideon several rows on a table of an adequate shape, or the one close to the other in various containers. The writings, numbers and /or designs are usually markedalong a circumference of the ogive and for each radius this circumference may have, the prolongation of the axis of the piercer always passes throughthe' axis of the cylinder and through the center of the are which defines the profile of the ogive. Moreover the axis of the piercer has to be aligned with the axis of a-hammering device which, acting on the head of the piercer, pushes its opposite end, i.e., that which represents the alpha-numerical sign or the de sign, in order to engrave the metallic surface to be marked. I

It is also known that the device supporting the piercers, after each engraving, shifts a littleforwards'of a pitch in orderto make room for the next piercer. In the same time the cylinder to be engraved rotates by a certain angle according to the space required between the various signs.

It is evident thatwith such an arrangement of the piercers the same symbol is always marked on each cylinder, where the meaning of the term symbol here and afterwards in the specification is a writing, number and/or design to be engraved. For the engraving of symbols which are possibly variable (such as the identification number, the weight value or thename of what is contained therein etc.) the manual substitution of the necessary piercers is carried out, with a resulting high waste of time. Otherwise the marking of the variable symbols or data on each cylinder is not effected at this stage but they will be subsequently hand-engraved with again a great waste of time and especially expensive handling operations of the pieces to be marked.

SUMMARY OF THE INVENTION The piercing machine according to the present invention is characterized in that the devicesupporting the piercers comprise a disc on which the piercers are placed in a spiral arrangement this disc supporting the piercers is operated, during its rotation, by two different and independent mechanisms, one for the engraving of fixed symbols, i.e., those which have to be impressed in the same succession of signs for each cylinder of the same lot, and the'other mechanism for the operation of the disc during the engraving of the variable symbols on each cylinder.

The first mechanism consists of a ratchet gear which impresses an intermittent mono-directional rotation movement of a constant angular amplitude corresponding to the space between two contiguous piercers. The second mechanism consists of a cylinder-piston system operating a rack which meshes with a pinion gear integral with the shaft of the disc supporting the piercers, which is capable of a continuous rotation, in both directions, by angle values corresponding to the angle existing between contiguous piercers or multiples thereof.

An important advantage of the piercing machine according to the present invention when compared with the machines of the prior art is given by the fact that if the size and the total number of piercers are the same, the disc is less encumbering and in consequence has a lower inertia when subjected to the frequent, quick and intermittent rotations which occur in the succession of the piercers under the hammering device during the engraving process.

Another important advantage of the piercing machine according to the present invention is given by the uniform and simple kind of movementof the disc during the succession of all piercers, i.e., an intermittent rotation at a constant angular value'which is combined with a uniform translation of the axis of the disc in respect of the hammering device, in order to maintain coaxial therewith the engraving piercer, irrespective of its position along'theabove-mentioned spiral. The translation of the disc axis is obtainedby a cam rotating in phase with the same disc bearing the piercers and having a spiral profile, in particular shaped as an Archimedean spiral, the radius of which increases according to a law identical to that of the spiral along which the piercers are arranged. j

A further advantage of the piercing machine accord: ing to the present invention is given by the fact that it is possible to engrave writings along different, coaxial circumferences of the ogive while the disc bearing the piercers continues its regular and uniform movement. In fact, cylinders are usually engraved along two, three, four or five circumference arcs having the centers on the axis of the cylinder itself and angular amplitudes usually in the range between about and For this arrangement of the marking, in order to avoid idle time when running along wide angle shots uselessly-, the,

cylinder first rotates intermittently in one direction in order to be engraved on the first circumference, then the cylinder reverses the direction 'of its rotation and the second circumference is engraved in the opposite sense. This being'over, the rotation direction is again inverted and so on. The disc bearing the piercers on the contrary always rotates in the-same direction, being nevertheless the piercers arranged on the disc according to the required succession for the symbols of the first, third and fifth circumferences and in the reversed succession for the symbols to be engraved on the ogive on the,second and fourth circumferences.

Other kinds of writings onthe ogives can be marked, if desired in order to cover, for example, two circular sectors being diametrically opposed on. the sa'mecin cumference. In such cases, the rotation of the cylinder is mono-directional and the piercers are all arranged on the disc according to a sole succession. The rotation of the cylinder in the two sectors of the writing will be relatively slow and intermittent owing to the space between two contiguous types of writing, while it will be quick and continuous in correspondence with the two sectors wherein no mark must be impressed.

The cylinder to be engraved is supported in any previously known manner and for example, at the nose portion by a sleeve which also gives the drive for the required rotation to mutually space the various types of a writing and on the opposite side of the cylinder, by an appropriate idle funnel or operated by an oloedynamic piston. It is to be noted that the operating means for beating the piercers can consist of an electromagnetic hammer, being particularly capable of giving a beating force adequate to each piercer, as that described in the Italian Patent No. 859256 in the name of the same Assignee.

BRIEF DESCRIPTION OF THE DRAWINGS These and other objects, advantages and features of the piercing machine according to the present invention will be evident to those skilled in the art by the following detailed description of a preferred embodiment given as a non-limiting example with reference to the annexed drawings in which:

FIG. 1 schematically represents the disc bearing the piercers together with the two devices for operating the rotation of the disc;

FIG. 2 schematically represents the succession according to which the piercers are arranged on the disc;

FIGS. 3a and 312 respectively represent two views, which are perpendicular each other, of the device for the movement of the axis of the disc bearing the piercers; and

FIG. 4 represents a schematic view of the overall piercing machine, with particular regard to the support means of the cylinder and to the device for operating the movement of an anvil adapted to contrast the knocking on the piercer.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, the disc 1 bearing the piercers is shown together with the two devices for giving the rotation drive i.e., the ratchet gear for the monodirectional intermittent rotation and the rack-piston system for the continuous rotation in both directions i.e., clockwise and counterclockwise, as viewed. The dotted line 2 represents the spiral, in particular an Archimedean spiral, along which the holes 3 are provided on the disc, suitably spaced apart, and therein the piercers (not show in FIG. I) are inserted,

The mechanism for operating the mono-directional and intermittent rotation movement of the disc I bearing the piercers comprises a piston-cylinder 5 the piston rod 5' of which operates a tooth 4 ofa ratchet gear meshing with the toothed periphery 12 of the disc 1 in order to cause the same disc to rotate by an angle corresponding to the space between two contiguous signs, whenever the cylinder 5 is operated. On the piston-rod 5, through a bush 6, a pawl 7 is fixed, pivotedly mounted in 8, having the function of locking in a working position the disc I after each thrust imparted by the ratchet gear 4. During the operation of the latter, the pawl 7, when rotating around the pivot 8, disengages from the teeth 12 of the disc 1, while during the idle reversal stroke or the tooth 4, it operates again by locking the disc in the required working position in correspondence of which the portion of the ogive to be engraved, the piercer to be beaten and the hammering device are all positioned on the same axis.

On the shaft of the disc 1 there is keyed a pinion 9 which meshes with a rack 10 driven by a piston rod 11 slidably mounted within a double-acting cylinder 11.

Upon the disengagement of tooth 4 and pawl 7, this cylinder 11 enables the rotation of the disc 1 in both the directions in order to select thepiercers, relative to the variable symbols, to be positioned in the proper succession under the hammering device. The required rotation in the required direction is given to the disc 1 by the system rack 10 cylinder 11 piston 11' through an oleodynamic control device actuated by a known two-way electrovalve not shown in the drawing. The slide shutter of the electrovalve is electrically controlled in either directions by electric signals preferably transmitted by a usual memory being preset, for example, through a manual keyboard actuated by an operator which reports the variable symbols previously written on each cylinder, such as by chalk.

The operation of the piercing machine according to the present invention may be completely automated when said memory, instead of being set by a keyboard manually controlled by the operator, can be directly set in input by a control weightometer positioned before the piercing machine, by which the variables of each cylinder (weight and capacity) are measured and moreover the identification number of the container is allotted.

FIG. 2 schematically represents the manner in which the piercers are arranged on the disc 1 according to an example of marking bothfixed and variable symbols. In correspondence with the axis of the cylinder and the hammering device, schematically represented by a hammer, there is positioned the first piercer of the symbol to be engraved, being the disc represented in the starting position. After fourteen piercers arranged according to a sequence order correponding to that of the fixed symbol, all referred to as a, ten piercers are mounted bearing FIGS. 1, 2, 3 8, 9, 0, referred to as b, by which the identification number of the cylinder can be completed, the first figures of which are given by the last four piercers of the group a. Then another group of piercers follows, which relate to a second fixed symbol, referred to as a, a second series of figures b, by which any number for representing the capacity and/or the weight value of the cylinder can be composed. Finally there is a third group of types of marks for another fixed symbol, referred to as a".

In the illustrated example, the piercers have been represented, through their respective signs, on a spiral which for graphic convenience includes less than one turn. However, it is obvious that, according to the invention, the piercers may be arranged along one or more turns of a spiral.

The disc 1, operated by the ratchet gear 4, starts the intermittent rotation in the sense of an arrow F, by constant angles, the amplitude of which corresponds to the pitch or interval between two adjacent piercers. In this way, on the ogive of the cylinder, which in synchronism rotates in an intermittent manner according to the arrow G, the signs of the group a are engraved with the same sequence order with which the piercers are arranged on the disc.

Subsequently, in order to complete the identification number, the first figures of which are included in the fixed symbol a as they must be substituted only after a great number of cylinders have been submitted to the piercing machine, the ratchet gear 4 is disengaged, for example through a device 13 as shown in FIG. 1, and the system piston-rack is operated. By means of this latter system and with the aid of the pre-set memory, the disc will rotate of suitable angle values in order to bring successively under the hammer the piercers of the group b having the required figures to complete the identification number of the cylinder during this engravingstage, for example the 'two figures corresponding to the tens and units represented in heavy types in FIG. 2 of the drawings; of course the'last figure of the identification riumber is variable at each cylinder, the last but one figure is variable every ten cylinders and so on.

After having engraved the last variable figure, the rack 10, controlled by the memory, will cause the disc 1 to rotate until it brings under the hammer the first piercer of the second fixed symbol a which in this case bears the letter 0" from the word oxygen. After having engraved this sign, the rotation of the disc by means of the rack is disconnected and the ratchet gear 4 is again automatically actuated, for example through the device 13. The ratchet gear will operate the rotation of the disc step by step until the group of signs a is completed. Then, by changing again the control device of the disc, the series of signs for the second variable symbol b' indicating the capacity and the'weight, will be engraved, for example:

42.4 Liters 41.7 Kg by selecting as already described, one after the other, the piercers bearing the required signs. The disc in such cases, as before during the completion of the identification number, can rotate not only in the normal advancing direction F, but also in the opposite one represented by the arrow F.

Referring now to FIGS. 3a and 3b, the disc 1 bearing the piercers 14 to be beaten by the hammer 16, e.g., of the electromagnetic type, in order to engrave the ogive of the cylinder 15, rotates by means of the ratchet gear 4 or the rack (cfr. FIG. 1) around a central axis 17, being supported by a slide 18 running in both senses along a pair of guides 19. The rotation movement of the disc 1 is transmitted to a cam 20 by means of a pair of toothed wheels 21 and 22. The periphery of the'cam 20 is constantly in engagement with a fixed abutment 23 and since the cam 20 is pivotedly mounted on the slide 18, each rotation of said cam causes a traverse of the slide itself and therefore of the disc 1 according to a law which is a function of the profile shape of the cam 20. If the cam 20 has a spiral-shaped profile, the radius of which increases according'to a law identical to that of the spiral along which the piercers 14 are arranged on the disc I, the shifting of the disc 1 bearing the piercers is such that the piercer to be beaten is always coaxial with the hammer 16.

Referring now to FIG. 4, a cylinder is represented during the piercing operation being supported by two end bearings 24 and 25, at least one of which is a driving means'and such as to cause the cylinder to rotate intermittently in the sense of the arrow G.

An anvil or wedge 26 for taking up the beating force ispushed by a piston 27 along an inclined-plane 28 and is positioned underthe cylinder 15 when this latter'has completed the necessary rotation for enabling the usualspace between two subsequent signs. After the hammer 16 has beaten the corresponding piercer 14, the wedge 26 is again pushed backwards being moved away from the cylinder thus allowing the subsequent rotation.

Further additions and/or modifications can be brought by those skilled in the art to the abovedescribed and illustrated embodiment of the piercing machine according to the present invention, without exceeding the scope of the same invention. In particular, the devices according to the present invention, while are described and illustrated with reference to the use for engraving metallic cylinders, can be conveniently used for engraving various writings on any curved surface.

What I claim is: 1. A machine for engraving of types or marks on curved metallic surfaces comprising a disc,

a plurality of piercers mounted on said disc in a spiral arrangement, a hammering means for beating on a selected one of said piercers in a fixed position, means for supporting and rotating the metallic surface to be engraved, first means for intermittently rotating said disc in a mono-direction in a step-by-step sequence, each' said step corresponding with an angular space between two adjacent piercer's, second means for rotating said disc in a selected one of a clockwise and counterclockwise direction over an angle corresponding to at least one angular space between two adjacent piercers, said piercers being perpendicular to the plane of said disc, and further comprising displacement means for displacing said disc in said plane. I

2. A machine according to claim 1, wherein said piercers are associated with fixed symbols for each subsequent metallic surface to be engraved and are arranged on said disc and along said spiral shape accord ing to a subsequence order corresponding exactly to that of the fixed symbol to be engraved.

3. A machine according to claim 1', wherein said device for supporting and rotating the metallic surface to be engraved comprises means for rotating said metallic surface intermittently in one of a clockwise and counterclockwise direction.

4. A machine according to claim 3, further comprising an anvil means for taking up the force of said hammering means on the piercer and means for bringing said anvil into contact with said metallic surface in a means itself, and for-disengaging said anvil upon the beating of the hammering means and before the following operation of said supporting and rotating device for causing the subsequent sign to be engraved on the metallic surface.

5. A machine according to claim 1 wherein said disc has a toothed periphery and said first means comprises a ratchet gear adapted to engage the toothed periphery of said disc, said ratchet gear being operated by a cylinder-piston system having a-piston rod also adapted to act on a locking pawl by disengaging said pawl from said toothed periphery during the operation of said v.ratchet gear.

6. A machine according to claim 1v wherein said disc ismounted on arotatable shaft and said means comfile of said cam has a spiral-shape the radius of which increases according to a law being the same as that of the spiral along which said piercers are arranged on said disc, whereby the displacement of the disc always allows for the complete correspondence and the maxi ality between each of the piercer and the hammering means for beating thereon. 

1. A machine for engraving of types or marks on curved metallic surfaces comprising a disc, a plurality of piercers mounted on said disc in a spiral arrangement, a hammering means for beating on a selected one of said piercers in a fixed position, means for supporting and rotating the metallic surface to be engraved, first means for intermittently rotating said disc in a monodirection in a step-by-step sequence, each said step corresponding with an angular space between two adjacent piercers, second means for rotating said disc in a selected one of a clockwise and counterclockwise direction over an angle corresponding to at least one angular space between two adjacent piercers, said piercers being perpendicular to the plane of said disc, and further comprising displacement means for displacing said disc in said plane.
 2. A machine according to claim 1, wherein said piercers are associated with fixed symbols for each subsequent metallic surface to be engraved and are arranged on said disc and along said spiral shape according to a subsequence order corresponding exactly to that of the fixed symbol to be engraved.
 3. A machine according to claim 1, wherein said device for supporting and rotating the metallic surface to be engraved comprises means for rotating said metallic surface intermittently in one of a clockwise and counterclockwise direction.
 4. A machine according to claim 3, further comprising an anvil means for taking up the force of said hammering means on the piercer and means for bringing said anvil into contact with said metallic surface in a position which is coaxial with said hammering means and said piercer before the operation of the hammering means itself, and for disengaging said anvil upon the beating of the hammering means and before the following operation of said supporting and rotating device for causing the subsequent sign to be engraved on the metallic surface.
 5. A machine according to claim 1 wherein said disc has a toothed periphery and said first means comprises a ratchet gear adapted to engage the toothed periphery of said disc, said ratchet gear being operated by a cylinder-piston system having a piston rod also adapted to act on a locking pawl by disengaging said pawl from said toothed periphery during the operation of said ratchet gear.
 6. A machine according to claim 1 wherein said disc is mounted on a rotatable shaft and said means comprises a pinion fixed on said shaft and meshing with a rack operated by a doubleacting cylinder-piston system.
 7. A machine according to claim 1 wherein said displacement means comprises a cam rotatably connected to said disc and having a profile resting on a fixed abutment and being pivotedly mounted on a reciprocating slide running along fixed guides.
 8. A machine according to claim 7, wherein the profile of said cam has a spiral-shape the radius of which increases according to a law being the same as that of the spiral along which said piercers are arranged on said disc, whereby the displacement of the disc always allows for the complete correspondence and the coaxiality between each of the piercer and the hammering means for beating thereon. 